AT&T had a secret program that can help law enforcement acquire relevant information to aid their investigation without the need to obtain a search warrant, according to a Business Insider report.

But with current news reports, it looks like the “cat is out of the bag.”

Through the program called Hemisphere, law enforcement can obtain call metadata on targeted individuals that will only require an administrative subpoena to access database. It only requires a government agent to declare the information they try to acquire could be “relevant” to an investigation.

According to The Daily Beast report, Hemisphere is a secretive program run by AT&T that searches trillions of call records and analyzes cellular data to determine where a target is located, with whom he speaks, and potentially why.

The Department of Justice said Hemisphere was an essential counter-narcotics tool if prudently deployed. In 2013 the New York Times revealed it was used on more than just drug-related cases. It was reportedly used on homicides to Medicaid fraud. No warrant is needed, but requires a promise from law enforcement not to disclose the program if an investigation using it becomes public.

Hemisphere was born on 2007, the same year that AT&T came under fire due to handing mined records over to the FBI. The records were obtained using a company invented programming language that could mine its own records for information.

Currently, Hemisphere is used in at least 28 intelligence centers across the country. Law enforcement has no direct access to AT&T’s data.

The Daily Beast posted a statement attributed to AT&T that says, “The Government agency agrees not to use the data as evidence in any judicial or administrative proceedings unless there is no other available and admissible probative evidence.”

This means that investigators have to make what is known as “parallel construction” by providing the same evidence through their routine police work while using the lead provided by AT&T acquired through Hemisphere.

The Electronic Frontier Foundation, American Civil Liberties Union, and Electronic Privacy Information Center have all expressed concern that surveillance using Hemisphere is unconstitutionally intrusive, and have sought more information on the program, with little success.

In December 2015, a group of shareholders filed a proposal to require the company to issue a statement “clarifying the Company’s policies regarding providing information to law enforcement and intelligence agencies, domestically and internationally, above and beyond what is legally required by court order or other legally mandated process.”

AT&T disputed the proposal and is now before the Securities and Exchange Commission.